 /*******************************************************************************
  * Copyright (c) 2004, 2005 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  * IBM Corporation - initial API and implementation
  *******************************************************************************/
 package org.eclipse.core.runtime.preferences;

 import org.eclipse.core.runtime.IPath;

 /**
  * Clients implement this interface to provide context to a
  * particular scope. Instances of implementations of this interface are
  * passed to the {@link IPreferencesService} for use in
  * preference searching.
  * <p>
  * Clients may implement this interface.
  * </p>
  *
  * @see IPreferencesService
  * @since 3.0
  */
 public interface IScopeContext {

     /**
      * Return the name of the scope that this context is associated with.
      * Must not be <code>null</code>.
      *
      * @return the name of the scope
      */
     public String getName();

     /**
      * Return the preferences node that contains the preferences for the
      * given qualifier or <code>null</code> if the node cannot be determined.
      * The given qualifier must not be <code>null</code> but may be a path
      * to a sub-node within the scope.
      * <p>
      * An example of a qualifier in Eclipse 2.1 would be the plug-in identifier that
      * the preference is associated with (e.g. the "org.eclipse.core.resources"
      * plug-in defines the "description.autobuild" preference).
      * </p><p>
      * This method can be used to determine the appropriate preferences node
      * to aid in setting key/value pairs. For instance:
      * <code>new InstanceScope().getNode("org.eclipse.core.resources");</code>
      * returns the preference node in the instance scope where the preferences
      * for "org.eclipse.core.resources" are stored.
      * </p>
      * @param qualifier a qualifier for the preference name
      * @return the node containing the plug-in preferences or <code>null</code>
      * @see IPreferencesService
      */
     public IEclipsePreferences getNode(String qualifier);

     /**
      * Return a path to a location in the file-system where clients are able
      * to write files that will have the same sharing/scope properties as
      * preferences defined in this scope.
      * <p>
      * Implementors may return <code>null</code> if the location is not known,
      * is unavailable, or is not applicable to this scope.
      * </p>
      * @return a writable location in the file system or <code>null</code>
      */
     public IPath getLocation();
 }

